FARGO (AP) - A woman who worked at a treatment center for young adults sent a 16-year-old boy several text messages, including one that said, "I wuv u 2," authorities say in court documents charging her with sexual assault and harboring a runaway minor.

Kimberly Nack, 28, of Fargo, was charged Friday in East Central District Court. Authorities said she and the 16-year-old boy met while she was working as a counselor at Luther Hall, a treatment center for young people. She also has worked as a truant officer in the Moorhead, Minn., School District.

Investigators found the youth at Nack's apartment on Dec. 23, court documents show. Nack told authorities that she let him use her apartment because he had been kicked out of his home.

Investigators said Nack acknowledged kissing the boy and allowing him to fondle her when the two of them were watching movies at the apartment.

A text message from the boy to Nack read, "My mom finally called me on luving u. I didn't give anything away but she cried anyway. Gee, another 6 hrs of fun. Oh well," authorities said in court documents.

Nack recently resigned from her job at Luther Hall, which is run by Lutheran Social Services of North Dakota.